The present invention relates to a vibration-proof device for an optic source element of upper transparency adapter, and particularly to a vibration-proof device used in a scanner having an upper transparency adapter (UTA) for preventing noises caused by the optic source element of the UTA.
FIG. 1 is a lateral view of a conventional scanner equipped with an UTA, in which the scanner mainly includes a casing 200 having a top being installed with a glass panel 45. A chassis 60 is installed within the casing 200. The chassis 60 is movably coupled to a slide lever 70 disposed inside the casing 200 for moving forwards and backwards along the slide lever 70 under the glass panel 45. An image sensing device (not shown) retained in the chassis 60 serves to scan a document 50 disposed over the glass panel 45. The image sensing device is generally equipped with a an image detector such as CCD, CIS or CMOS (compensated metal oxide semiconductor).
As illustrated in FIG. 1, an upper transparency adapter (UTA) is formed by a cover 100 attached to the top of the casing 200 and an optic source clement 10 mounted in the cover 100. The optic source element 10 is movably coupled to a slide lever 20 disposed in the cover 100 for moving synchronously with the chassis 60, and serves as a light source as the document 50 positioned over the glass panel 45 is transparent, in order for the image sensing device to sense the image on the document 50. As shown in the drawing, the optic source element 10 consists of a sliding carriage 14 and a light source 12 associated with the sliding carriage 14 for illuminating the document 50. Consequently, the light source 12 is capable of being moved alone the glass panel 40 so as to illuminate light to pass through the document 50 placed thereunder, while the sliding carriage 14 is driven to move along the slide rod 20 The sliding carriage 14 is generally arranged with an AC to DC converter (not shown) and the light source 12 has a lamp electrically coupled to the AS to DC converter and a light-reflecting plate (not shown).
FIG. 2 is a partial perspective view of a conventional upper transparency adapter, in which only a slide rod 20 disposed at the center of the casing 100 is illustrated. As shown in the drawing, one end of the slide rod 20 is firmly secured to a support 26xe2x80x2 attached to the inner surface of the casing 100, and the sliding carriage 14 slidably coupled to the slide rod 20 is joined to a driving belt 25. The driving belt 25 is wound around a pulley 23 proximate to the support 26xe2x80x2 and driven by a servo motor (not shown) allowing the sliding carriage 14 to be driven by the driving belt 25 to slide along the slide rod 20.
Referring to FIG. 3, the slide rod 20 is firmly secured to the support 26xe2x80x2 with bolts 29 which securely fix the support 26xe2x80x2 to the posts 28xe2x80x2 protruded from the inner surface of the casing 100. Due to the lack of manufacturing and assembling precision a gap G is usually formed between the light source 12 and the glass panel 40. As abovementioned, the sliding carriage 14 is movably coupled to the slide rod 20 and the light source 12 are radially outwardly extended toward the opposing sidewalls of the casing 150, so that when the driving belt 25 drives the optic source element 10 to slidably move along the slide rod 20, the light source 12 tends to swing or oscillate to thereby cause the light source 12 to irregularly come in touch with the glass panel 40. When the light source 12 irregularly comes in touch with the glass panel 40 during the moving course, noises will generate.
Furthermore, the swing or oscillation of the light source 12 during the scanning operation, not only generates the noise, but also adversely affects the scanning quality.
Accordingly, the present invention has been designed for overcoming the shortcomings of the aforementioned conventional upper transparency adapter. The primary objective of the present invention is to provided a vibration-proof device that prevents the optic source element disposed in an upper transparency adapter of a scanner from swing or oscillating, thus eliminating noise when the scanner is in operation.
Another objective of the present invention is to provide a vibration-proof device that can prevent the optic source element disposed in an upper transparency adapter of a scanner from swinging or oscillating, thus assuring the scanning quality.
In accordance with the above and other objectives, the present invention provides a vibration-proof device for an optic source disposed in an upper transparency adapter of a scanner, wherein the upper transparency adapter is secured to a casing of the scanner, to allow the scanner to scan a transparent document. The upper transparency adapter is composed of a cover attached to the top of the scanner, the optic source element mounted in the cover, a glass panel installed on the bottom of the cover and a slide rod mounted in the cover to which the optic source element is coupled, allowing the optic source element to slidably move along the glide rod proximate to the glass panel.
The vibration-proof device of the present invention comprises a supporter for coupling the slide rod, a positioning member erected from a base of the cover toward the glass panel for retaining the supporter in place in the cover, and an elastic member interposed between the supporter and the base of the cover so as to resiliently support the supporter to thereby constantly abut the optic source element against the glass panel by an appropriate elastic force rendered by the elastic member.
At the end of the positioning member facing the glass panel is formed with an enlarged portion for preventing the supporter from escaping from the positioning member. Since a conventional bolt is generally in a shape of elongated post with a head having a diameter greater than that of the post, so it can serve as the positioning member for the purpose of reducing production and assembly costs. Furthermore, the positioning member may be directly screwed into the cover, or screwably engaged with an engaging post protruded from an inner surface of the cover facing the glass panel.
The elastic member may be a spring, an elastic cylindrical rod, or the like and is adapted for sleeving the positioning member or the engaging post for engagement with the positioning member.
The supporter is formed with at least a hole for the insertion of the positioning member, so it can be slidably retained in position along the axial direction of the positioning member and resiliently supported by the elastic member for constantly abut the optic source element coupled to the slide rod connected with the supporter against the glass panel.